Electronic cooling has been a major impediment for system size reduction and often dictates external dimensions and form factors for computers and other equipments. Electronic systems are generally provided with a large number of heat-generating components such as, for example, microprocessors, power amplifiers, radio frequency (RF) devices and high-power lasers. The functional integrity of such electronic components can be maintained by keeping the temperature of these components below a predetermined value.
An air cooled heat exchanger can be utilized for efficient heat transfer from heat-generating components to ambient air. Conventional heat exchangers rely on an external air-moving component such as, for example, a blower or a fan, to provide airflow for convective heat transfer. For example, the heat exchanger for a CPU (Central Processing Unit) cooling in a desktop computer includes the use of a finned heatsink and a fan. A problem associated with such heat exchangers is the poor heat transfer from the fins surface to the laminar air stream and low efficiency of external air moving units such as blowers or fans. As such, they are very inefficient in terms of the amount of heat removal per unit power consumption, known as a coefficient of performance (COP), which may be typically lower than ten. Such low efficiency, or COP, often results in heavy, bulky, and noisy thermal management systems.
In one prior art implementation, a large total fin area is needed to achieve sufficient fin-air heat transfer and low thermal resistance. However, for a given heatsink size, the large fin area requires a dense placement of the fins which leads to a higher pressure drop and a higher power consumption by the blowers or the fans. Commercially available blowers and fans for electronic cooling, particularly in the high pressure regime, have low efficiencies, typically converting less than 20% of the electrical energy to air pressure while the majority to turbulence. The turbulence in the external blowers or fans is quickly dissipated into heat long before it enters the fin channels to perform any useful work, which therefore is wasted. In addition, the overall size of the heat exchangers is significantly increased due to the size of the external blowers or fans.
Based on the foregoing it is believed that a need exists for an improved heat exchanger that can be adapted for enhanced heat transfer applications in electronic components based on micro-jet entrainment as described in greater detail herein.